Such a control device may, for example, be used in an aircraft having a jet engine or turboprop engine.
This control device can control both the engine power and a thrust reverser device. A thrust reverser device is a device that directs the engine thrust in the forward direction in order to decelerate the aircraft and reduce braking distance during landing.
This control device generally comprises a lever for adjusting the power, commonly called a throttle lever or thrust lever, and a thrust reverser lever, both of which are adapted to pivot between an idle position and a fully actuated position in order to rotate a control member. Sensors, cooperating with the control member, are adapted to transmit control commands to a control unit.
The most recent control devices can provide a function in which, when one lever is positioned within a certain angular range of its actuation path, any simultaneous manipulation of the other lever is blocked by a mechanical type of prevention.
For example, in patent application WO 2011/042147, this prevention is achieved by sliding a finger simultaneously into a first cam track formed in the structure and into a second cam track formed on a part integral to the control member of the device; the finger being arranged in an elongated groove formed at the end of the thrust lever and being connected by a rod to the thrust reverser lever. When manipulating the thrust reverser lever and the thrust lever, the finger slides in the grooves of the first and second cam tracks and thereby causes the thumbwheel to rotate.
Such a control device has good mechanical strength. However, it can induce high mechanical stress at certain functional points, requiring the overdesigning of certain parts. This overdesigning is critical because of the location of these parts in the kinematic chain. Such overdesigning can also increase the weight of the control device. Such a control device is also complex to implement when high precision is desired in the angle of rotation of a lever from which point the other lever is prevented from rotating.
Also known, for example from patent application WO 2011/042146, is an “engaging roller” system which, in the same system, further implements a second function of automatically returning a lever to its idle position if it is positioned before a predefined angle of its actuation path and if the other lever is actuated.
Such an “engaging roller” type of system allows providing two functions with one subassembly, which lowers the number of parts, the bulk, the weight, and the cost. However, such a system has a lower mechanical strength and achieves the desired levels of locking precision only through the use of an adjustment system that is difficult to manage because of assembly tolerances and machining precisions.